How severe is CVE-2025-62801?

CVE-2025-62801 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2025-62801 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (11th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-62801?

CVE-2025-62801 affects Jlowin Fastmcp. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-62801?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2025-62801 have an EU (EUVD) identifier?

Yes. CVE-2025-62801 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-36567.

When was CVE-2025-62801 published?

CVE-2025-62801 was published on 2025-10-28 and last updated on 2026-06-17.

CVE-2025-62801

CVE-2025-62801 is a high-severity vulnerability in Jlowin Fastmcp with a CVSS 3.x base score of 7.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-78.

Key facts

Severity: High (CVSS 3.x base score 7.8)
CVSS v4: 5.4
EPSS exploit prediction: 0% (11th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-36567
Weakness: CWE-78
Affected product: Jlowin Fastmcp
Published: 2025-10-28
Last modified: 2026-06-17

Description

FastMCP is the standard framework for building MCP applications. Versions prior to 2.13.0, a command-injection vulnerability lets any attacker who can influence the server_name field of an MCP execute arbitrary OS commands on Windows hosts that run fastmcp install cursor. This vulnerability is fixed in 2.13.0.

Frequently asked questions

What is CVE-2025-62801?: FastMCP is the standard framework for building MCP applications. Versions prior to 2.13.0, a command-injection vulnerability lets any attacker who can influence the server_name field of an MCP execute arbitrary OS commands on Windows hosts that run fastmcp install cursor. This vulnerability is fixed in 2.13.0.
How severe is CVE-2025-62801?: CVE-2025-62801 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2025-62801 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (11th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-62801?: CVE-2025-62801 affects Jlowin Fastmcp. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-62801?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2025-62801 have an EU (EUVD) identifier?: Yes. CVE-2025-62801 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-36567.
When was CVE-2025-62801 published?: CVE-2025-62801 was published on 2025-10-28 and last updated on 2026-06-17.

References

https://github.com/jlowin/fastmcp/security/advisories/GHSA-rj5c-58rq-j5g5

Affected products (1)

cpe:2.3:a:jlowin:fastmcp:*:*:*:*:*:*:*:*

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